Robot for simultaneous substrate transfer

ABSTRACT

Exemplary substrate processing systems may include a transfer region housing defining an internal volume. A sidewall of the transfer region housing may define a sealable access for providing and receiving substrates. The systems may include a plurality of substrate supports disposed within the transfer region. The systems may also include a transfer apparatus having a central hub including a first shaft and a second shaft concentric with and counter-rotatable to the first shaft. The transfer apparatus may include a first end effector coupled with the first shaft. The first end effector may include a plurality of first arms. The transfer apparatus may also include a second end effector coupled with the second shaft. The second end effector may include a plurality of second arms having a number of second arms equal to the number of first arms of the first end effector.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. Non-Provisional patentapplication Ser. No. 16/922,447, filed 7 Jul. 2020, which claims thebenefit of priority of U.S. Provisional Patent Application No.62/873,400, filed 12 Jul. 2019, the contents of which are herebyincorporated by reference in its entirety for all purposes. The presenttechnology is further related to the following applications, allconcurrently filed 12 Jul. 2019, and titled: “ROBOT FOR SIMULTANEOUSSUBSTRATE TRANSFER” (U.S. Provisional Patent Application No.62/873,432), “ROBOT FOR SIMULTANEOUS SUBSTRATE TRANSFER” (U.S.Provisional Patent Application No. 62/873,458), “ROBOT FOR SIMULTANEOUSSUBSTRATE TRANSFER” (U.S. Provisional Patent Application No.62/873,480), “MULTI-LID STRUCTURE FOR SEMICONDUCTOR PROCESSING SYSTEMS”(U.S. Provisional Patent Application No. 62/873,518), and “HIGH-DENSITYSUBSTRATE PROCESSING SYSTEMS AND METHODS” (U.S. Provisional PatentApplication No. 62/873,503). Each of these applications is herebyincorporated by reference in their entirety for all purposes.

TECHNICAL FIELD

The present technology relates to semiconductor processes and equipment.More specifically, the present technology relates to substrateprocessing systems.

BACKGROUND

Semiconductor processing systems often utilize cluster tools tointegrate a number of process chambers together. This configuration mayfacilitate the performance of several sequential processing operationswithout removing the substrate from a controlled processing environment,or it may allow a similar process to be performed on multiple substratesat once in the varying chambers. These chambers may include, forexample, degas chambers, pretreatment chambers, transfer chambers,chemical vapor deposition chambers, physical vapor deposition chambers,etch chambers, metrology chambers, and other chambers. The combinationof chambers in a cluster tool, as well as the operating conditions andparameters under which these chambers are run, are selected to fabricatespecific structures using particular process recipes and process flows.

Cluster tools often process a number of substrates by continuouslypassing substrates through a series of chambers and process operations.The process recipes and sequences will typically be programmed into amicroprocessor controller that will direct, control, and monitor theprocessing of each substrate through the cluster tool. Once an entirecassette of wafers has been successfully processed through the clustertool, the cassette may be passed to yet another cluster tool orstand-alone tool, such as a chemical mechanical polisher, for furtherprocessing.

Robots are typically used to transfer the wafers through the variousprocessing and holding chambers. The amount of time required for eachprocess and handling operation has a direct impact on the throughput ofsubstrates per unit of time. Substrate throughput in a cluster tool maybe directly related to the speed of the substrate handling robotpositioned in a transfer chamber. As processing chamber configurationsare further developed, conventional wafer transfer systems may beinadequate.

Thus, there is need for improved systems and methods that can be used toefficiently direct substrates within cluster tool environments. Theseand other needs are addressed by the present technology.

SUMMARY

Exemplary substrate processing systems may include a transfer regionhousing defining a transfer region. A sidewall of the transfer regionhousing may define a sealable access for providing and receivingsubstrates. The systems may include a plurality of substrate supportsdisposed within the transfer region. The systems may also include atransfer apparatus. The transfer apparatus may include a central hubincluding a first shaft and a second shaft extending about andconcentric with the first shaft. The second shaft may becounter-rotatable with the first shaft. The transfer apparatus mayinclude a first end effector coupled with the first shaft. The first endeffector may include a plurality of first arms having a number of firstarms equal to a number of substrate supports of the plurality ofsubstrate supports. The transfer apparatus may also include a second endeffector coupled with the second shaft. The second end effector mayinclude a plurality of second arms having a number of second arms equalto the number of first arms of the first end effector.

In some embodiments, the plurality of substrate supports may include atleast four substrate supports. The second end effector may be verticallyoffset from the first end effector along the central hub. The first endeffector may also include a plurality of first end pieces, each firstend piece coupled with a separate first arm of the plurality of firstarms. The second end effector may also include a plurality of second endpieces, each second end piece coupled with a separate second arm of theplurality of second arms. Each first end piece and each second end piecemay extend vertically to a similar plane extending orthogonally to thecentral hub. Each first end piece and each second end piece may define arecessed ledge and a shelf Each first end piece and each second endpiece may be characterized by an arcuate exterior profile. Each firstend piece may include a force-generating plunger configured toreleasably engage a substrate against a corresponding second end piece.The central hub may be vertically translatable along a central axis ofthe central hub.

Some embodiments of the present technology may include methods oftransferring a substrate. The methods may include receiving a substrateat a first substrate support within a transfer region of a substrateprocessing system. The substrate processing system may include atransfer apparatus. The transfer apparatus may include a central hubincluding a first shaft and a second shaft extending about andconcentric with the first shaft. The transfer apparatus may include afirst end effector coupled with the first shaft, and the first endeffector may include a plurality of first arms. The transfer apparatusmay also include a second end effector coupled with the second shaft,and the second end effector may include a plurality of second arms. Themethods may include rotating the first shaft in a first direction abouta central axis of the central hub. The methods may include rotating thesecond shaft in a second direction about the central axis of the centralhub. The methods may include engaging the substrate with a first arm ofthe plurality of first arms and a second arm of the plurality of secondarms. The methods may include co-rotating the first arm and the secondarm about the central axis to reposition the substrate. The methods mayalso include delivering the substrate to a second substrate support ofthe substrate processing system.

In some embodiments, the methods may include disengaging the substratefrom the transfer apparatus by rotating the first shaft in the seconddirection about the central axis and rotating the second shaft in thefirst direction about the central axis. The methods may include,subsequent engaging the substrate, lifting the substrate from the firstsubstrate support by translating the transfer apparatus verticallywithin the transfer region. The methods may include, subsequent engagingthe substrate, recessing the first substrate support from the substrate.The first end effector may include a plurality of first end pieces, eachfirst end piece coupled with a separate first arm of the plurality offirst arms. The second end effector may include a plurality of secondend pieces, each second end piece coupled with a separate second arm ofthe plurality of second arms. Each first end piece and each second endpiece may define a recessed ledge and a shelf. Engaging the substratemay include extending the shelf of the first end piece of the first armand the shelf of the second end piece of the second arm beneath anexterior edge of the substrate. The substrate processing system mayinclude at least four substrates, and engaging the substrate may includesimultaneously engaging the at least four substrates with the first endeffector and the second end effector. The methods may also include,prior to delivering the substrate to the second substrate support,delivering the substrate to an alignment hub positioned between thefirst substrate support and the second substrate support.

Some embodiments of the present technology may include substrateprocessing systems including a transfer region housing defining atransfer region. A sidewall of the transfer region housing may define asealable access for providing and receiving substrates. The systems mayinclude a plurality of substrate supports disposed within the transferregion. The systems may include a transfer apparatus. The transferapparatus may include a central hub including a first shaft and a secondshaft extending about and concentric with the first shaft. The secondshaft may be independently rotatable from the first shaft. The transferapparatus may include a first end effector coupled with the first shaft.The first end effector may include a plurality of first arms extendingradially outward from the central hub to a distal end of each first armof the plurality of first arms. Each first arm may be characterized byan arcuate shape extending along a first arc path to the distal end ofeach first arm. The transfer apparatus may include a second end effectorcoupled with the second shaft. The second end effector may include aplurality of second arms extending radially outward from the central hubto a distal end of each second arm of the plurality of second arms. Eachsecond arm may be characterized by an arcuate shape extending along asecond arc path to the distal end of each second arm. The second arcpath may be the first arc path mirrored about a lateral axis extendingfrom the central hub normal to a central axis of the central hub.

In some embodiments, the first end effector may include a plurality offirst end pieces, each first end piece coupled with a separate first armof the plurality of first arms. The second end effector may also includea plurality of second end pieces, each second end piece coupled with aseparate second arm of the plurality of second arms. The central hub maybe vertically translatable along the central axis of the central hub.

Such technology may provide numerous benefits over conventional systemsand techniques. For example, the handling systems may provide increasedtransfer speeds compared to conventional designs. Additionally, thehandling systems may accommodate transfer regions having multiple rowsof substrates. These and other embodiments, along with many of theiradvantages and features, are described in more detail in conjunctionwith the below description and attached figures.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the disclosedtechnology may be realized by reference to the remaining portions of thespecification and the drawings.

FIG. 1A shows a schematic top plan view of an exemplary processingsystem according to some embodiments of the present technology.

FIG. 1B shows a schematic partial cross-sectional view of an exemplarychamber system according to some embodiments of the present technology.

FIG. 2 shows a schematic perspective view of a transfer region of anexemplary chamber system according to some embodiments of the presenttechnology.

FIGS. 3A-3B show schematic cross-sectional views of exemplary transferapparatuses according to some embodiments of the present technology.

FIG. 4 shows exemplary operations in a method of transferring substratesaccording to some embodiments of the present technology.

FIGS. 5A-5H show schematic top plan views of substrates beingtransferred according to some embodiments of the present technology.

FIGS. 6A-6B show schematic views of substrate seating according to someembodiments of the present technology.

Several of the figures are included as schematics. It is to beunderstood that the figures are for illustrative purposes, and are notto be considered of scale or proportion unless specifically stated to beof scale or proportion. Additionally, as schematics, the figures areprovided to aid comprehension and may not include all aspects orinformation compared to realistic representations, and may includeexaggerated material for illustrative purposes.

In the appended figures, similar components and/or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a letter thatdistinguishes among the similar components. If only the first referencelabel is used in the specification, the description is applicable to anyone of the similar components having the same first reference labelirrespective of the letter.

DETAILED DESCRIPTION

Substrate processing can include time-intensive operations for adding,removing, or otherwise modifying materials on a wafer or semiconductorsubstrate. Efficient movement of the substrate may reduce queue timesand improve substrate throughput. To improve the number of substratesprocessed within a cluster tool, additional chambers may be incorporatedonto the mainframe. Although transfer robots and processing chambers canbe continually added by lengthening the tool, this may become spaceinefficient as the footprint of the cluster tool scales. Accordingly,the present technology may include cluster tools with an increasednumber of processing chambers within a defined footprint. To accommodatethe limited footprint about transfer robots, the present technology mayincrease the number of processing chambers laterally outward from therobot. For example, some conventional cluster tools may include one ortwo processing chambers positioned about sections of a centrally locatedtransfer robot to maximize the number of chambers radially about therobot. The present technology may expand on this concept byincorporating additional chambers laterally outward as another row orgroup of chambers. For example, the present technology may be appliedwith cluster tools including three, four, five, six, or more processingchambers accessible at each of one or more robot access positions.

However, as additional process locations are added, accessing theselocations from a central robot may no longer be feasible withoutadditional transfer capabilities at each location. Some conventionaltechnologies may include wafer carriers on which the substrates remainseated during transition. However, wafer carriers may contribute tothermal non-uniformity and particle contamination on substrates. Thepresent technology overcomes these issues by incorporating a transfersection vertically aligned with processing chamber regions and acarousel or transfer apparatus that may operate in concert with acentral robot to access additional wafer positions. The presenttechnology may not use conventional wafer carriers in some embodiments,and may transfer specific wafers from one substrate support to adifferent substrate support within the transfer region. Although theremaining disclosure will routinely identify specific structures, suchas four-position transfer regions, for which the present structures andmethods may be employed, it will be readily understood that the systemsand methods are equally applicable to any number of structures anddevices that may benefit from the transfer capabilities explained.Accordingly, the technology should not be considered to be so limited asfor use with any particular structures alone. Moreover, although anexemplary tool system will be described to provide foundation for thepresent technology, it is to be understood that the present technologycan be incorporated with any number of semiconductor processing chambersand tools that may benefit from some or all of the operations andsystems to be described.

FIG. 1A shows a top plan view of one embodiment of a substrateprocessing tool or processing system 100 of deposition, etching, baking,and curing chambers according to some embodiments of the presenttechnology. In the figure, a set of front-opening unified pods 102supply substrates of a variety of sizes that are received within afactory interface 103 by robotic arms 104 a and 104 b and placed into aload lock or low pressure holding area 106 before being delivered to oneof the substrate processing regions 108, positioned in chamber systemsor quad sections 109 a-c, which may each be a substrate processingsystem having a transfer region fluidly coupled with a plurality ofprocessing regions 108. Although a quad system is illustrated, it is tobe understood that platforms incorporating standalone chambers, twinchambers, and other multiple chamber systems are equally encompassed bythe present technology. A second robotic arm 110 housed in a transferchamber 112 may be used to transport the substrate wafers from theholding area 106 to the quad sections 109 and back, and second roboticarm 110 may be housed in a transfer chamber with which each of the quadsections or processing systems may be connected. Each substrateprocessing region 108 can be outfitted to perform a number of substrateprocessing operations including any number of deposition processesincluding cyclical layer deposition, atomic layer deposition, chemicalvapor deposition, physical vapor deposition, as well as etch, pre-clean,anneal, plasma processing, degas, orientation, and other substrateprocesses.

Each quad section 109 may include a transfer region that may receivesubstrates from, and deliver substrates to, second robotic arm 110. Thetransfer region of the chamber system may be aligned with the transferchamber having the second robotic arm 110. In some embodiments thetransfer region may be laterally accessible to the robot. In subsequentoperations, components of the transfer sections may vertically translatethe substrates into the overlying processing regions 108. Similarly, thetransfer regions may also be operable to rotate substrates betweenpositions within each transfer region. The substrate processing regions108 may include any number of system components for depositing,annealing, curing and/or etching a material film on the substrate orwafer. In one configuration, two sets of the processing regions, such asthe processing regions in quad section 109 a and 109 b, may be used todeposit material on the substrate, and the third set of processingchambers, such as the processing chambers or regions in quad section 109c, may be used to cure, anneal, or treat the deposited films. In anotherconfiguration, all three sets of chambers, such as all twelve chambersillustrated, may be configured to both deposit and/or cure a film on thesubstrate.

As illustrated in the figure, second robotic arm 110 may include twoarms for delivering and/or retrieving multiple substratessimultaneously. For example, each quad section 109 may include twoaccesses 107 along a surface of a housing of the transfer region, whichmay be laterally aligned with the second robotic arm. The accesses maybe defined along a surface adjacent the transfer chamber 112. In someembodiments, such as illustrated, the first access may be aligned with afirst substrate support of the plurality of substrate supports of a quadsection. Additionally, the second access may be aligned with a secondsubstrate support of the plurality of substrate supports of the quadsection. The first substrate support may be adjacent to the secondsubstrate support, and the two substrate supports may define a first rowof substrate supports in some embodiments. As shown in the illustratedconfiguration, a second row of substrate supports may be positionedbehind the first row of substrate supports laterally outward from thetransfer chamber 112. The two arms of the second robotic arm 110 may bespaced to allow the two arms to simultaneously enter a quad section orchamber system to deliver or retrieve one or two substrates to substratesupports within the transfer region.

Any one or more of the transfer regions described may be incorporatedwith additional chambers separated from the fabrication system shown indifferent embodiments. It will be appreciated that additionalconfigurations of deposition, etching, annealing, and curing chambersfor material films are contemplated by processing system 100.Additionally, any number of other processing systems may be utilizedwith the present technology, which may incorporate transfer systems forperforming any of the specific operations, such as the substratemovement. In some embodiments, processing systems that may provideaccess to multiple processing chamber regions while maintaining a vacuumenvironment in various sections, such as the noted holding and transferareas, may allow operations to be performed in multiple chambers whilemaintaining a particular vacuum environment between discrete processes.

FIG. 1B shows a schematic cross-sectional elevation view of oneembodiment of an exemplary processing tool, such as through a chambersystem, according to some embodiments of the present technology. FIG. 1Bmay illustrate a cross-sectional view through any two adjacentprocessing regions 108 in any quad section 109, such as illustratedthrough line A-A in FIG. 1A. The elevation view may illustrate theconfiguration or fluid coupling of one or more processing regions 108with a transfer region 120. For example, a continuous transfer region120 may be defined by a transfer region housing 125. The housing maydefine an open interior volume in which a number of substrate supports130 may be disposed. For example, as illustrated in FIG. 1A, exemplaryprocessing systems may include four or more, including a plurality ofsubstrate supports 130 distributed within the housing about the transferregion. The substrate supports may be pedestals as illustrated, althougha number of other configurations may also be used. In some embodimentsthe pedestals may be vertically translatable between the transfer region120 and the processing regions overlying the transfer region. Thesubstrate supports may be vertically translatable along a central axisof the substrate support along a path between a first position and asecond position within the chamber system. Accordingly, in someembodiments each substrate support 130 may be axially aligned with anoverlying processing region 108 defined by one or more chambercomponents.

The open transfer region may afford the ability of a transfer apparatus135, such as a carousel, to engage and move substrates, such asrotationally, between the various substrate supports. The transferapparatus 135 may be rotatable about a central axis. This may allowsubstrates to be positioned for processing within any of the processingregions 108 within the processing system. The transfer apparatus 135 mayinclude one or more end effectors that may engage substrates from above,below, or may engage exterior edges of the substrates for movement aboutthe substrate supports. The transfer apparatus may receive substratesfrom a transfer chamber robot, such as robot 110 described previously.The transfer apparatus may then rotate substrates to alternate substratesupports to facilitate delivery of additional substrates.

Once positioned and awaiting processing, the transfer apparatus mayposition the end effectors or arms between substrate supports, which mayallow the substrate supports to be raised past the transfer apparatus135 and deliver the substrates into the processing regions 108, whichmay be vertically offset from the transfer region. For example, and asillustrated, substrate support 130 a may deliver a substrate intoprocessing region 108 a, while substrate support 130 b may deliver asubstrate into processing region 108 b. This may occur with the othertwo substrate supports and processing regions, as well as withadditional substrate supports and processing regions in embodiments forwhich additional processing regions are included. In this configuration,the substrate supports may at least partially define a processing region108 from below when operationally engaged for processing substrates,such as in the second position, and the processing regions may beaxially aligned with an associated substrate support. The processingregions may be defined from above by a faceplate 140, as well as otherlid stack components. In some embodiments, each processing region mayhave individual lid stack components, although in some embodimentscomponents may accommodate multiple processing regions 108. Based onthis configuration, in some embodiments each processing region 108 maybe fluidly coupled with the transfer region, while being fluidlyisolated from above from each other processing region within the chambersystem or quad section.

In some embodiments the faceplate 140 may operate as an electrode of thesystem for producing a local plasma within the processing region 108. Asillustrated, each processing region may utilize or incorporate aseparate faceplate. For example, faceplate 140 a may be included todefine from above processing region 108 a, and faceplate 140 b may beincluded to define from above processing region 108 b. In someembodiments the substrate support may operate as the companion electrodefor generating a capacitively-coupled plasma between the faceplate andthe substrate support. A pumping liner 145 may at least partially definethe processing region 108 radially, or laterally depending on the volumegeometry. Again, separate pumping liners may be utilized for eachprocessing region. For example, pumping liner 145 a may at leastpartially radially define processing region 108 a, and pumping liner 145b may at least partially radially define processing region 108 b. Ablocker plate 150 may be positioned between a lid 155 and the faceplate140 in embodiments, and again separate blocker plates may be included tofacilitate fluid distribution within each processing region. Forexample, blocker plate 150 a may be included for distribution towardsprocessing region 108 a, and blocker plate 150 b may be included fordistribution towards processing region 108 b.

Lid 155 may be a separate component for each processing region, or mayinclude one or more common aspects. In some embodiments, such asillustrated, lid 155 may be a single component defining multipleapertures 160 for fluid delivery to individual processing regions. Forexample, lid 155 may define a first aperture 160 a for fluid delivery toprocessing region 108 a, and lid 155 may define a second aperture 160 bfor fluid delivery to processing region 108 b. Additional apertures maybe defined for additional processing regions within each section whenincluded. In some embodiments, each quad section 109—ormulti-processing-region section that may accommodate more or less thanfour substrates, may include one or more remote plasma units 165 fordelivering plasma effluents into the processing chamber. In someembodiments individual plasma units may be incorporated for each chamberprocessing region, although in some embodiments fewer remote plasmaunits may be used. For example, as illustrated a single remote plasmaunit 165 may be used for multiple chambers, such as two, three, four, ormore chambers up to all chambers for a particular quad section. Pipingmay extend from the remote plasma unit 165 to each aperture 160 fordelivery of plasma effluents for processing or cleaning in embodimentsof the present technology.

As noted, processing system 100, or more specifically quad sections orchamber systems incorporated with system 100 or other processingsystems, may include transfer regions positioned below the processingchamber regions illustrated. FIG. 2 shows a schematic isometric view ofan exemplary substrate processing system 200 according to someembodiments of the present technology. The system illustrated mayinclude a transfer region housing 205 defining an internal volume ortransfer region in which a number of components may be included. Thetransfer region may additionally be at least partially defined fromabove by processing chambers, such as processing chambers illustrated inquad sections 109 of FIG. 1A. A sidewall of the transfer region housingmay define one or more access locations 207 through which substrates maybe delivered and retrieved, such as by second robotic arm 110 asdiscussed above. Access locations 207 may be slit valves or othersealable access positions, which include doors or other sealingmechanisms to provide a hermetic environment within transfer regionhousing 205 in some embodiments. Although illustrated with two suchaccess locations 207, it is to be understood that in some embodimentsonly a single access location 207 may be included. It is also to beunderstood that substrate processing system 200 may be sized toaccommodate any substrate size, including 200 mm, 300 mm, 450 mm, orlarger or smaller substrates, including substrates characterized by anynumber of geometries or shapes.

Within transfer region housing 205 may be a plurality of substratesupports 210 positioned about the transfer region volume. Although foursubstrate supports are illustrated, it is to be understood that anynumber of substrate supports are similarly encompassed by embodiments ofthe present technology. For example, greater than or about three, four,five, six, eight, or more substrate supports 210 may be accommodated intransfer regions according to embodiments of the present technology.Second robotic arm 110 may deliver a substrate to either or both ofsubstrate supports 210 a or 210 b through the accesses 207, and maydeliver substrates directly to a transfer apparatus within the transferregion in some embodiments. Similarly, second robotic arm 110 mayretrieve substrates from these locations. Lift pins 212 may protrudefrom the substrate supports 210, and may allow the robot to accessbeneath the substrates. The lift pins may be fixed on the substratesupports, or at a location where the substrate supports may recessbelow, or the lift pins may additionally be raised or lowered throughthe substrate supports in some embodiments. Substrate supports 210 maybe vertically translatable, and in some embodiments may extend up toprocessing chambers, such as processing chambers 108, positioned abovethe transfer region housing 205.

The transfer region housing 205 may provide access for alignment systems215, which may include an aligner that can extend through an aperture ofthe transfer region as illustrated and may operate in conjunction with alaser, camera, or other monitoring device protruding or transmittingthrough an adjacent aperture, and that may determine whether a substratebeing translated is properly aligned. Transfer region housing 205 mayalso include a transfer apparatus 220 that may be operated in a numberof ways to position substrates and move substrates between the varioussubstrate supports. Although exemplary operations will be describedbelow, in one example, transfer apparatus 220 may move substrates onsubstrate supports 210 a and 210 b to substrate supports 210 c and 210d, which may allow additional substrates to be delivered into thetransfer region.

Transfer apparatus 220 may include a central hub 225 that may includeone or more shafts extending into the transfer region. Coupled with thecentral hub may be a first end effector 230, and a second end effector235. First end effector 230 may include a plurality of first arms 233extending radially or laterally outward from the central hub. Similarly,second end effector 235 may include a plurality of second arms 237extending radially or laterally outward from the central hub. Althoughillustrated with a central body from which the arms extend, each of theend effectors may additionally include separate arms that are eachcoupled with the central hub 225. Any number of arms may be included inembodiments of the present technology. In some embodiments a number offirst arms 233 may be similar or equal to the number of substratesupports 210 included in the chamber, and the number of second arms 237may be similar or equal to the number of first arms 233. Hence, asillustrated, for four substrate supports, transfer apparatus 220 mayinclude four arms for each of the first end effector and the second endeffector. The arms may be characterized by any number of shapes andprofiles, such as straight profiles, as well as arcuate profiles asillustrated. Although any profile may be utilized, in some embodimentsan arcuate profile may accommodate a substrate, which may be circular insome embodiments.

When used, the arcuate profiles of the first arms of the first endeffector may be characterized by a particular arc profile extendingalong an edge of each first arm to a distal end of the first arm.Additionally, the second arms of the second end effector may also becharacterized by a particular arc profile extending along an edge ofeach second arm to a distal end. However, the arc profile of the secondarms may be reversed or mirrored from the arc profile of the first arms,which may accommodate an opposite edge of a substrate being transferred.The mirroring may be along an axis extending radially or laterallyoutward from the central hub between a first arm of the first endeffector and a second arm of the second end effector, such as an axisnormal to a central axis extending vertically through the central hub.Consequently, in some embodiments the second end effector may be aninverted version of the first end effector as illustrated.

The first end effector 230 may additionally include a plurality of firstend pieces 240. Each first end piece 240 may be coupled with a separatefirst arm of the plurality of first arms 233. Similarly, second endeffector 235 may additionally include a plurality of second end pieces242. Each second end piece 242 may be coupled with a separate second armof the plurality of second arms 237. Each end piece may also becharacterized by an arcuate exterior profile to accommodate a circularor otherwise arcuate substrate. The end pieces will be described in moredetail below, and may be used to contact substrates during transfer ormovement. The end pieces as well as the end effectors may be made fromor include a number of materials including conductive and/or insulativematerials. The materials may be coated or plated in some embodiments towithstand contact with precursors or other chemicals that may pass intothe transfer region from an overlying processing chamber.

Additionally, the materials may be provided or selected to withstandother environmental characteristics, such as temperature. In someembodiments, the substrate supports may be operable to heat a substratedisposed on the support. The substrate supports may be configured toincrease a surface or substrate temperature to temperatures greater thanor about 100° C., greater than or about 200° C., greater than or about300° C., greater than or about 400° C., greater than or about 500° C.,greater than or about 600° C., greater than or about 700° C., greaterthan or about 800° C., or higher. Any of these temperatures may bemaintained during operations, and thus components of the transferapparatus 220 may be exposed to any of these stated or encompassedtemperatures. Consequently, in some embodiments any of the materials maybe selected to accommodate these temperature regimes, and may includematerials such as ceramics and metals that may be characterized byrelatively low coefficients of thermal expansion, or other beneficialcharacteristics. Component couplings may also be adapted for operationin high temperature and/or corrosive environments. For example, whereend effectors and end pieces are each ceramic, the coupling may includepress fittings, snap fittings, or other fittings that may not includeadditional materials, such as bolts, which may expand and contract withtemperature, and may cause cracking in the ceramics. In some embodimentsthe end pieces may be continuous with the end effectors, and may bemonolithically formed with the end effectors. Any number of othermaterials may be utilized that may facilitate operation or resistanceduring operation, and are similarly encompassed by the presenttechnology.

The transfer apparatus 220 may include a number of components andconfigurations that may facilitate the movement of the end effectors aswill be described further below. FIGS. 3A-3B show schematiccross-sectional views of exemplary transfer apparatus 220 according tosome embodiments of the present technology, although it is to beunderstood that any other configurations affording the independentrotational movement to be described are similarly encompassed by thepresent technology.

Central hub 225 may include a first shaft 310 and a second shaft 320,which may be axially aligned with first shaft 310. For example, firstshaft 310 and second shaft 320 may be concentric about a central axisextending vertically through the central hub. In some embodiments firstshaft 310 may extend through second shaft 320, or aspects of secondshaft 320. As illustrated in FIG. 3A, first shaft 310 and second shaft320 may be coaxial, although the two shafts may be coupled with separatemotor or drive systems. As illustrated, first shaft 310 a may be coupledwith a first drive system 312 a, which may include a motor, and whichmay allow rotation about the central axis, which may rotate first endeffector 230 in a first direction about the central axis, or in a seconddirection opposite the first. Similarly, second shaft 320 a may becoupled with a second drive system 314 a, which may independently allowrotation of second end effector 235 in the first direction or the seconddirection about the central axis. In some embodiments a verticaltranslation drive 325 may be included, which may allow the transferapparatus to be vertically translated along the central axis. This mayfacilitate lifting substrates from substrate supports or lift pins insome embodiments, although in some embodiments the lift pins and/orsubstrate supports may be used to raise and lower substrates, andtransfer apparatus 220 may not include a vertical drive mechanism.

FIG. 3B illustrates another embodiment of transfer apparatus 220 whichmay utilize a gear box to facilitate counter rotation of the first shaft310 b relative to the second shaft 320 b. For example, second shaft 320b may be coupled with a gear box 330 including a gear set 332 having afirst gear coupled with the first shaft 310 b. As would be readilyunderstood, driving the first gear in a first direction with first drivesystem 312 b would produce a counter rotation in the opposite gear,which may be coupled with second shaft 320 b and second end effector235. Additionally, a second drive system 314 b may be coupled with thecomponents to rotate the gear box and first shaft together, which wouldfacilitate co-rotation of the end effectors. The figure also shows theoptional vertical translation drive 325, which may linearly move thetransfer apparatus up or down as described above. It is to be understoodthat FIGS. 3A-3B are merely illustrative of any number of configurationsand components that may be used to independently rotate the first shaftand second shaft affording separate control of the first end effectorand second end effector. Consequently, in some embodiments the firstshaft and second shaft may be co-rotated about the central axis, or thetwo shafts may be counter-rotated with respect to the other shaft. Thisoperation will be described in more detail below.

As illustrated in both figures, the first end effector 230 and thesecond end effector 235 may be vertically offset from one another alongthe central hub in some embodiments. This may offset associatedcomponents in some embodiments, such as the first end pieces and thesecond end pieces. Accordingly, the present technology may furthermodify the first end pieces and the second end pieces to accommodate thevertical offset of the first end effector and the second end effector aswill be described further below.

FIG. 4 shows exemplary operations in a method 400 of transferring asubstrate according to some embodiments of the present technology.Method 400 may be performed in one or more transfer systems, such assystem 200, which may be incorporated into processing system 100, forexample. The method may include a number of optional operations asdenoted in the figure, which may or may not be specifically associatedwith some embodiments of methods according to the present technology.Method 400 describes operations shown schematically in FIGS. 5A-5H, theillustrations of which will be described in conjunction with theoperations of method 400. It is to be understood that FIG. 5 illustratesonly partial schematic views with limited details, and in someembodiments the systems may include more or less substrate supports andother components, as well as alternative structural aspects that maystill benefit from any of the aspects of the present technology.

FIG. 5A may illustrate a substrate processing system 500 as previouslydescribed, and may include any of the features and aspects of substrateprocessing system 200 described above, including any of the drivecomponents discussed previously with FIG. 3 , as well as any other drivecomponents as would be understood are similarly encompassed by thepresent technology. Additionally, system 500 may be illustrated with anumber of substrates 501 disposed within the chamber, such as seated onsubstrate supports 510 as illustrated. The figure may show aconfiguration of the present technology subsequent initial operations ofmethod 400, which may include receiving a substrate at a first substratesupport 510 a at operation 405, such as through an access with a robotas previously described. The robot may deliver one or two, or more,substrates into the transfer region 205 onto the substrate supportsproximate the accesses or slit valves. Transfer apparatus 220 may rotatethe two substrates to the opposite substrate supports, and twoadditional substrates may be delivered. It is to be understood that thesame process can be performed with any number of substrates, includingdelivery of one substrate at a time into the processing chamber. FIG. 5Amay illustrate after four substrates have been positioned within thetransfer region, and the transfer apparatus 220 may be positioned in arecessed configuration.

A transfer process may involve rotating the transfer apparatus in anumber of ways. For example, to engage the substrates, the method mayinclude rotating the first shaft of the central hub in a first directionabout a central axis of the central hub at operation 410. Previously,subsequently, or concurrently, the method may include rotating thesecond shaft in a second direction about the central axis of the secondhub at operation 415. The second direction may be the opposite rotationof the first direction as previously described. The rotation maycontinue until a first arm 233 of the first end effector 230 and asecond arm 237 of the second end effector 235 engage a substrate atoperation 420, as illustrated in FIG. 5B.

Depending on the transfer apparatus having vertical movementcapabilities or not, the movement and engagement may or may not includeraising or lowering one or both of the substrates or the transferapparatus. Additionally, engaging the substrate may include one or moreoperations including a passive engagement and an active engagement insome embodiments. For example, as will be explained further below, theend pieces of the first end effector and the second end effector mayinclude a variety of forms facilitating engagement. In one form ofpassive engagement, the end pieces may define a recessed ledge and shelfon which a substrate may be seated. Accordingly, with end pieces in thisconfiguration, the first arms and second arms may counter rotate towardsthe substrate until a shelf of each end piece extends below an edge ofthe substrate. In a form of active engagement, one or both of the endpieces may physically and/or forcibly engage a substrate, includingcompressing or clamping the substrate between the end pieces. When morethan one substrate is incorporated within the transfer region, thesubstrates may be simultaneously engaged as illustrated in FIG. 5B.Because the arms may be equidistantly distributed about the central hub,the arms may be configured to engage all substrates together.

Once the substrates have been engaged by the transfer apparatus, acomplete transfer of the substrate or substrates may be made between thesubstrate supports and the transfer apparatus. For example, in someembodiments the transfer apparatus may lift the substrates in optionaloperation 425, and from the substrate supports or lift pins on which thesubstrates may be seated. This may be performed by verticallytranslating the transfer apparatus, for example. In some embodiments,the substrate supports may recess away from the substrate or substratesto complete the transfer.

After the transfer is complete to the transfer apparatus, the substratesmay be rotated between the substrate supports for further processing indifferent chambers, or to deliver the substrates to substrate supportsaccessible by a transfer robot, such as second robotic arm 110 describedabove. Translation of the substrate or substrates may occur at operation430, and as illustrated in FIG. 5C. Although the figure illustrates acounterclockwise rotation, it is to be understood that the substratescan be rotated in either direction about the central axis inembodiments. The rotational translation of the substrates may beperformed by co-rotating the first arm 233 and the second arm 237 at acommon rate to maintain the engagement of the substrate 501. Asillustrated, the co-rotation may occur along the second direction aboutthe central axis. Consequently, the direction of rotation of the firstshaft may be reversed, while the rotation of the second shaft maycontinue in the same direction as used for engagement. Of course, iftranslation of the substrate proceeded along the first direction, thedirections of the shaft rotation would be the opposite as well.

As previously noted, substrate processing systems according toembodiments of the present technology may have monitoring and alignmentsystems, including an alignment hub 540 positioned between each pair ofsubstrate supports. Additional access port 542 may allow a camera orlaser to impinge on the substrate to identify misalignment, which couldbe based on a notch or other identifier on the substrate. In someembodiments an optional alignment operation may be performed on each ofthe substrates at optional operation 435. In some embodiments, thetransfer apparatus may release the substrates onto an aligner when thesubstrates have been translated over the alignment devices asillustrated in FIG. 5D. One or more of the aligners, depending on howmany substrates are being translated, may protrude into the transferregion and receive the substrates. An alignment adjustment may beperformed, and the transfer apparatus may re-engage the substrates.

Additionally illustrated in FIG. 5D may be an aspect of the transferregion to accommodate the rotation of the substrate through the chamber.As illustrated, during rotation the substrate may pass a zenith positionin between adjacent substrate supports. While transfer region 205 may berectilinear, a path of rotation may be elliptical or circular asillustrated. In some embodiments, transfer region 205 may be largeenough to extend beyond the path of rotation. However, in someembodiments, transfer region 205 may include an accommodation along thepath where a recess 550 may be formed in the transfer region wall tolimit or prevent impact between a substrate 501 being translated and awall of the transfer region. Such a recess 550 may be formed in eachwall of the transfer region in some embodiments.

As illustrated in FIG. 5E, the transfer apparatus may continue to rotatethe substrates towards a substrate support to which the substrate 501 isto be delivered. Although illustrating a transfer to an adjacentsubstrate support in a counterclockwise direction, it is to beunderstood that delivery to any other substrate support in eitherrotational direction may similarly be performed. At operation 440 thesubstrate 501 may be delivered to a second substrate support 510 b asillustrated in FIG. 5F. Once delivered, the transfer apparatus maydisengage the substrate from the transfer apparatus. Again, thesubstrate may be lowered with the transfer apparatus, and/or thesubstrate support, or lift pins of the substrate support may engage thesubstrate to accept the substrate from the transfer apparatus.

The disengagement may also include rotating the first shaft and thesecond shaft in opposite directions from the original movements forengagement. For example, as illustrated in FIG. 5G, the first shaft maybe rotated in the second direction while the second shaft may be rotatedin the first direction to separate the first arms 233 of the first endeffector and the second arms 237 of the second end effector from oneanother away from the substrates. The arms may be rotated to a recessedconfiguration to avoid interaction with the substrate supports duringfurther processing as illustrated in FIG. 5H. Additionally, such aposition may align the arms of the first end effector and the second endeffector over the alignment hub 540 when included, which may provideprotection for the alignment hub against particle accumulation, forexample.

As previously noted, the transfer apparatus may include passive oractive engagement of the substrate with different end piececonfigurations. FIGS. 6A-6B show schematic views of substrate seatingaccording to some embodiments of the present technology. The figures mayinclude any aspect of the systems or transfer apparatuses describedpreviously, and may show additional aspects of components illustratedpreviously. Although the figures may illustrate an example of bothpassive and active engagement, it is to be understood that any number ofvariations may also be used, and are similarly encompassed by thepresent technology.

FIG. 6A illustrates an end elevation view, such as at a distal end of atransfer apparatus 600. The illustration may include a distal end of afirst arm 633 of a first end effector 630, as well as a distal end of asecond arm 637 of a second end effector 635. As previously explained,the first end effector 630 and second end effector 635 may be verticallyoffset from one another along the central hub. Although first endeffector 630 is illustrated above second end effector 635, it is to beunderstood the components could be reversed. A first end piece 640 maybe coupled with the first arm 633 of the first end effector 630, and asecond end piece 642 may be coupled with the second arm 637 of thesecond end effector 635 as previously described. FIG. 6A may illustratea passive engagement of substrate 601, in which a support surface isprovided, on which the substrate may be seated. Each of the first endpiece 640 and the second end piece 642 may define a recessed ledgeincluding a shelf portion extending towards an associated end piece forsubstrate support. First end piece 640 may define shelf 641 extendingtowards the associated second end piece 642, and second end piece 642may define shelf 643 extending towards the associated first end piece640. Together, the shelves may produce a wafer support surface about twoexterior or radial edges of substrate 601.

Although in some embodiments the first end piece and the second endpiece may be similar components, in some embodiments the two componentsmay be modified to account for the vertical offset of the end effectors.For example, despite the vertical offset of the end effectors, the firstend piece and the second end piece may extend vertically to a similarhorizontal plane through the central axis of the central hub.Accordingly, the first end piece and the second end piece may compensatefor the vertical offset to maintain or produce a substantially planarsurface for substrate support. Thus, first end piece 640 may extendvertically further than second end piece 642 to account for the offset.Hence, by this accommodation, shelf 641 and shelf 643 may besubstantially aligned along a horizontal plane.

FIG. 6B may illustrate an active engagement, which may facilitate fastertranslation because the substrate may not be susceptible to movementwith active engagement. The illustration may show transfer apparatus 650for supporting substrate 651. The components of the apparatus mayinclude a distal end of a first arm 663 of a first end effector 660, aswell as a distal end of a second arm 667 of a second end effector 665.Again as previously explained, the first end effector 660 and second endeffector 665 may be vertically offset from one another along the centralhub, and although first end effector 660 is illustrated above second endeffector 665, it is to be understood the components could be reversed. Afirst end piece 670 may be coupled with the first arm 663 of the firstend effector 660, and a second end piece 672 may be coupled with thesecond arm 667 of the second end effector 665 as previously described

Different from the end pieces of FIG. 6A, first end piece 670 and secondend piece 672 may be configured to contact an edge region of substrate651. Second end piece 672 may be configured to receive the substrateagainst a surface of the end piece, and may include a materialconfigured to support contact between the substrate and the end piecewithin the transfer region environmental conditions. First end piece 670may be configured to apply a force against the substrate 651 tomechanically, electrically, or otherwise seat the substrate against thesecond end piece. For example, first end piece 670 may include aspring-loaded or similar physical coupling plunger that may mechanicallyor otherwise force the substrate against the second end piece, and whichmay include a roller 674 or other component for directly contacting asubstrate. Additionally, the force-generating end piece may provide anelectrical coupling, such as by electrostatically engaging the substratealong component 674, which may be conductive or may otherwise facilitatethe coupling. In such a configuration, with the first end effectorcoupled with the interior shaft or first shaft, electrical leads may bedelivered through the first shaft of the central hub and out to firstend pieces 670 of each first arm without impacting any other componentof the central hub. Any number of other mechanical or attractive forcesmay be applied to releasably engage the substrate during transfer withinthe substrate processing system.

The present technology includes substrate processing systems that mayaccommodate additional substrate supports that may not otherwise beaccessible to centrally located transfer robots as previously described.By incorporating transfer apparatuses according to embodiments of thepresent technology, multiple substrate supports may be utilized andaccessed during substrate processing. When transfer apparatuses includefirst end effectors and second end effectors as described throughout thepresent technology, the movements to engage, transfer, and disengagewith substrates may all be performed along exterior edges of thesubstrates, which may facilitate avoiding lift pins along an interior ofthe substrate support. The systems may also provide increased transferspeeds by maintaining exterior contact and recess positions for the armsof the end effectors relative to the substrates.

In the preceding description, for the purposes of explanation, numerousdetails have been set forth in order to provide an understanding ofvarious embodiments of the present technology. It will be apparent toone skilled in the art, however, that certain embodiments may bepracticed without some of these details, or with additional details.

Having disclosed several embodiments, it will be recognized by those ofskill in the art that various modifications, alternative constructions,and equivalents may be used without departing from the spirit of theembodiments. Additionally, a number of well-known processes and elementshave not been described in order to avoid unnecessarily obscuring thepresent technology. Accordingly, the above description should not betaken as limiting the scope of the technology. Additionally, methods orprocesses may be described as sequential or in steps, but it is to beunderstood that the operations may be performed concurrently, or indifferent orders than listed.

Where a range of values is provided, it is understood that eachintervening value, to the smallest fraction of the unit of the lowerlimit, unless the context clearly dictates otherwise, between the upperand lower limits of that range is also specifically disclosed. Anynarrower range between any stated values or unstated intervening valuesin a stated range and any other stated or intervening value in thatstated range is encompassed. The upper and lower limits of those smallerranges may independently be included or excluded in the range, and eachrange where either, neither, or both limits are included in the smallerranges is also encompassed within the technology, subject to anyspecifically excluded limit in the stated range. Where the stated rangeincludes one or both of the limits, ranges excluding either or both ofthose included limits are also included.

As used herein and in the appended claims, the singular forms “a”, “an”,and “the” include plural references unless the context clearly dictatesotherwise. Thus, for example, reference to “a substrate” includes aplurality of such substrates, and reference to “the arm” includesreference to one or more arms and equivalents thereof known to thoseskilled in the art, and so forth.

Also, the words “comprise(s)”, “comprising”, “contain(s)”, “containing”,“include(s)”, and “including”, when used in this specification and inthe following claims, are intended to specify the presence of statedfeatures, integers, components, or operations, but they do not precludethe presence or addition of one or more other features, integers,components, operations, acts, or groups.

1. A substrate processing system comprising: a transfer region housingdefining a transfer region, wherein a sidewall of the transfer regionhousing defines a sealable access for providing and receivingsubstrates; a plurality of substrate supports disposed within thetransfer region; and a transfer apparatus comprising: a central hubincluding a first shaft and a second shaft extending about andconcentric with the first shaft, wherein the second shaft iscounter-rotatable with the first shaft, a first end effector coupledwith the first shaft, the first end effector comprising a plurality offirst arms having a number of first arms equal to a number of substratesupports of the plurality of substrate supports, wherein: the first endeffector further comprises a plurality of first end pieces; and eachfirst end piece of the plurality of first end pieces comprises a firstcontact member that engages a lateral surface of a substrate, and asecond end effector coupled with the second shaft, the second endeffector comprising a plurality of second arms having a number of secondarms equal to the number of first arms of the first end effector,wherein: the second end effector further comprises a plurality of secondend pieces; and each second end piece of the plurality of second endpieces comprises a second contact member that engages the lateralsurface of the substrate.
 2. The substrate processing system of claim 1,wherein each first contact member comprises a roller.
 3. The substrateprocessing system of claim 1, wherein: each first contact membercomprises an electrically conductive material; each first contact memberis coupled with one or more electrical leads; and each first contactmember generates an electrostatic force to engage the substrate.
 4. Thesubstrate processing system of claim 3, wherein the one of moreelectrical leads extend through the first shaft.
 5. The substrateprocessing system of claim 1, wherein each first contact member and eachsecond contact member extend vertically to a similar plane extendingorthogonally to the central hub.
 6. The substrate processing system ofclaim 1, wherein the first end effector and the second end effector arevertically offset relative to one another along the central hub.
 7. Thesubstrate processing system of claim 1, wherein each first end piece ofthe plurality of first end pieces comprises a spring loaded plunger thatis coupled with a respective one of the first contact members.
 8. Thesubstrate processing system of claim 1, wherein each first end piece isconfigured to releasably engage an edge of a substrate against acorresponding second end piece.
 9. The substrate processing system ofclaim 1, wherein the central hub is vertically translatable along acentral axis of the central hub.
 10. A method of transferring asubstrate, the method comprising: receiving a substrate at a firstsubstrate support within a transfer region of a substrate processingsystem, the substrate processing system including a transfer apparatuscomprising: a central hub including a first shaft and a second shaftextending about and concentric with the first shaft, a first endeffector coupled with the first shaft, the first end effector comprisinga plurality of first arms, wherein: the first end effector furthercomprises a plurality of first end pieces; and each first end piece ofthe plurality of first end pieces comprises a first contact member thatengages a lateral surface of a substrate, and a second end effectorcoupled with the second shaft, the second end effector comprising aplurality of second arms having a number of second arms equal to anumber of first arms of the first end effector, wherein: the second endeffector further comprises a plurality of second end pieces; and eachsecond end piece of the plurality of second end pieces comprises asecond contact member that engages the lateral surface of the substrate;rotating the first shaft in a first direction about a central axis ofthe central hub; rotating the second shaft in a second direction aboutthe central axis of the central hub; engaging the lateral surface of thesubstrate with the first contact member of a first respective arm of theplurality first arms and the second contact member of a secondrespective arm of the plurality of second arms; co-rotating the firstrespective arm and the second respective arm about the central axis toreposition the substrate; and delivering the substrate to a secondsubstrate support of the substrate processing system.
 11. The method oftransferring a substrate of claim 10, further comprising disengaging thesubstrate from the transfer apparatus by rotating the first shaft in thesecond direction about the central axis and rotating the second shaft inthe first direction about the central axis.
 12. The method oftransferring a substrate of claim 10, further comprising, subsequentengaging the substrate, lifting the substrate from the first substratesupport by translating the transfer apparatus vertically within thetransfer region.
 13. The method of transferring a substrate of claim 10,further comprising, subsequent engaging the substrate, recessing thefirst substrate support from the substrate.
 14. The method oftransferring a substrate of claim 10, wherein engaging the lateralsurface of the substrate comprises applying an electrostatic force tothe substrate via the first contact member of the first respective arm.15. The method of transferring a substrate of claim 14, wherein thelateral surface of the substrate comprises using a spring-loaded plungercoupled with the first contact member of the first respective arm tomechanically force the lateral surface of the substrate against thesecond contact member of the second respective arm.
 16. The method oftransferring a substrate of claim 10, wherein the substrate processingsystem includes at least four substrates, and wherein engaging thesubstrate comprises simultaneously engaging the at least four substrateswith the first end effector and the second end effector.
 17. The methodof transferring a substrate of claim 10, further comprising, prior todelivering the substrate to the second substrate support, delivering thesubstrate to an alignment hub positioned between the first substratesupport and the second substrate support.
 18. A substrate processingsystem comprising: a transfer region housing defining a transfer region,wherein a sidewall of the transfer region housing defines a sealableaccess for providing and receiving substrates; a plurality of substratesupports disposed within the transfer region; and a transfer apparatuscomprising: a central hub including a first shaft and a second shaftextending about and concentric with the first shaft, wherein the secondshaft is independently rotatable from the first shaft, a first endeffector coupled with the first shaft, the first end effector comprisinga plurality of first arms extending radially outward from the centralhub to a distal end of each first arm of the plurality of first arms,wherein: each first arm is characterized by an arcuate shape extendingalong a first arc path to the distal end of each first arm; the firstend effector further comprises a plurality of first end pieces; and eachfirst end piece of the plurality of first end pieces comprises a firstcontact member that engages a lateral surface of a substrate, and asecond end effector coupled with the second shaft, the second endeffector comprising a plurality of second arms extending radiallyoutward from the central hub to a distal end of each second arm of theplurality of second arms, wherein: the second end effector furthercomprises a plurality of second end pieces; each second end piece of theplurality of second end pieces comprises a second contact member thatengages the lateral surface of the substrate; each second arm ischaracterized by an arcuate shape extending along a second arc path tothe distal end of each second arm; and the second arc path is the firstarc path mirrored about a lateral axis extending from the central hubnormal to a central axis of the central hub.
 19. The substrateprocessing system of claim 18, wherein the central hub is verticallytranslatable along the central axis of the central hub.
 20. Thesubstrate processing system of claim 18, wherein the plurality ofsubstrate supports comprises at least four substrate supports.